Radiobiology

Whole Body Irradiation: The Hematopoietic Syndrome

The Bone Marrow Syndrome (Hematopoietic Syndrome)

Associated with exposures of at least 3 Gy (300 rad)
Mechanism: loss of pluripotent stem cells from hematopoietic tissues
Si/Sx: Pancytopenia, leading to infection and hemorrhage
Has a latency period 2-4 weeks
Rx: Blood products, bone marrow transplant, and antibiotics
Survival: 50% spontaneous recovery at exposure of 3.5 Gy. 180 days required to regain maximum function.
Few survive doses greater than 6-7 Gy (at doses above 8 Gy, >90% long-term immunosuppression is observed). Death is 1-2 months post-exposure from infection; anemia is not a cause of death